The use of signals from switches or sensors to control functional electrical stimulation (FES) of paralyzed muscles is known. Use of a shoulder position sensor to control wrist extension via an implanted FES stimulator has been described (Vodovnik, L. (1971) Development of Orthotic Systems using functional electrical stimulation and myoelectric control, Progress Report, University of Ljubljana, prepared for U.S. Dept. of Health Education and Welfare Social and Rehabilitation Service, under contract No. SRS-YUGO 23-68). Shoulder sensors have also been used to control hand opening and pinch-grip (Peckham, P. H., Marsolais, E. B. & Mortimer, J. T. (1980) J. Hand Surgery, 5,462-469; Peckham, P. H. & Keith, M. W. (1992) "Motor prostheses for restoration of upper extremity function" In: Neural Prostheses: Replacing Motor Function After Disease or Disability eds.: Stein, R. B., Peckham, P. H. & Popovic, D. B. New York: Oxford University Press; EP-145504-A, U.S. Pat. No. 4,558,704 and CA1263446-A, all of Wright State University. A wrist position sensor has been used to control FES of leg muscles (Prochazka, A. & Wiles, C. M. (1983) "Electrical stimulation of paretic leg muscles in man, allowing feedback-controlled movements to be generated from the wrist" J. Physiol. 343, 20P). A switch mounted on a watch band has been used to trigger FES--evoked pinch-grip (Handa, Y., Itchie, M., Handa, T., Takahashi, H. Saito, C., Kameyama, J. & Hoshimiya, N. (1989) "FES-control of multijoint system in the paralysed upper limb". Osaka Int. Workshop on FNS. pp. 91-95.). A multi-component device in which wrist position sensors are used to stimulate FES evoked pinch-grip has also been described (Crago, P. E., Peckham P. H., Mansour, J. M., Lan, N., Kilgore, K. and Chizeck, H. J. (1991) a, b, c,) "Functional neuromuscular stimulation for restoration of hand grasp" NIH Contract NO1-NS-9-2356 7th, 8th & 9th Progress Reports, June, September & December, 1991; Crago, P. E. Peckham, P. H. Mansour, J. M., Lan, N., Kilgore, K. and Chizeck, H. J. (1992). "Functional neuromuscular stimulation for restoration of hand grasp". NIH Contract NO1-NS-9-2356. 10th, 11th & 12th Progress Reports, March, June, September, 1992; Peckham, P. H. & Keith, M. W. (1992) "Motor prostheses for restoration of upper extremity function" In: Neural Prostheses: Replacing Motor Function After Disease or Disability, eds.: Stein, R. B., Peckham, P. H. & Popovic, D. B. New York: Oxford University Press). The use of FES to attenuate tremor was reported by Prochazka, A., Elek, J. and Javidan, M. (1992) "Attenuation of pathological tremors by functional electrical stimulatation" I. Technique, Annals of Biomedical Engineering, 20: 205-224.
Several of the approaches described above involve percutaneous wire electrodes, or fully implanted FES simulators i.e. invasive procedures are required to the hand and wrist in order to achieve a working system. Such previous systems also required extensive customization for each user using the systems and because they comprised several discrete components which required separate attachment to the patient, they were inconvenient to use. In none of the previous systems had a device been described which would permit movement-disabled persons to simply and independently don and remove a self-contained device for wrist-activated hand control.